“how the ten of them...”
Not to be nitpicky, but if you count the parents, there were actually 12 of them! Besides the Captain’s original 7 children, Georg and Maria had 2 girls while still living in Austria, in addition to the boy Maria was pregnant with when they fled. It’s quite a remarkable story.
The story might not have been quite as heartwarming as the film if they tried to film it literally, or if they had done so about their time after they left for the United States. One noteworthy difference between Maria and Georg von Trapp vs. their film counterparts was that the personalities were polar opposites. From what I understand, Maria was the martinet (indeed, she once locked up one of the eldest daughters to keep her away from a boyfriend, and it was crueler than it sounds) and Georg was warmer and fun-loving.
When the film was privately screened for the von Trapp family by the studio back in 1965, the members watching it derisively laughed at the portrayals and were apparently rolling in the aisles. The film von Trapps were nothing like the real ones.
A former internet acquaintance of mine from about a decade ago went to school with one of the von Trapp grandchildren, and he said they were anything but humble, and that they let the film go to their heads, so you can imagine the size of their ego.
As an aside, 14 years ago, I attended a film seminar with Robert Wise, the Academy Award winning director of the film (he also won for “West Side Story”), but I had to bite my tongue offering to pitch him my script idea for a sequel to the story of the von Trapps, set in 1960s Vermont. I’m sure he’d heard about a gazillion pitches for such an idea, both from 20th Century Fox and fans and screenwriters alike. Unfortunately, with Oscar Hammerstein’s death prior to the completion of the stage play (and Richard Rodgers later on), there was no way you could recreate the music that was so integral to the story, and I’m certainly no musician. ;-)